Weed screen explores options for grass-weed control
There is a need for a more programmed approach to tackling grass-weeds, in particular where black-grass is problematic.

Abby KellettAbby joined the arable team in 2015 having spent three years at Newcastle University studying Agriculture.
In between ...Load More
Abby KellettAbby joined the arable team in 2015 having spent three years at Newcastle University studying Agriculture.
In between ...Load More Share This
Find the right herbicide programme to control your grass-weeds #agronomy #arable
During the 2014/15 season Bayer CropScience tested a number of pre-emergence based treatments within its weed screen programme, which looked to minimise-grass weeds. With black-grass being one of the biggest challenges for the arable sector, it was the primary focus of the work, although pre-emergence, peri-emergence and post-emergence treatments were also tested against wild oats, sterile brome and other grass-weeds.
Results
- A simple programme based on a 0.6l/ha pre-emergence application of Liberator, (flufenacet+DFF) did a reasonable job across the spectrum but was not sufficient to control resistant black-grass. There was a need to add further components.
- A good mixture which had been extremely consistent was Liberator plus Defy (prosulfocarb) at 2l/ha, which lifted the level of control of resistant black-grass by 8-10 per cent compared to Liberator on its own.
- With a sequence of pre-emergence Liberator followed by peri-emergence Avadex (tri-allate) at 15g/ha, a 5-10 per cent improvement in black-grass control was observed.
- Where there was a severe black-grass problem, a more programmed approach was required. In addition to Liberator, an extra pre-em component should be applied as well as a follow-up post-emergence treatment when black-grass has 1-2 leaves. Atlantis (iodosulfuron+ mesosulfuron) at 4kg/ha, Liberator at 0.3l/ha+ Biopower at 1l/ha showed the best results across the full range of grass-weeds tested.
Click here to view access the weed-screen virtual tool
Commenting about the economic viability of using an extensive programmed approach, Bayer CropScience commercial technical manager Darren Adkins says “When talking about black-grass control you need to get approximately 97 per cent control of the weed in order to stand still, in other words, not increase the weed bank in the soil. In next-to-all cases this would mean using a programmed approach in order to achieve this.
“As a guide 12 black-grass plants per metre squared will reduce wheat yield by about 0.5 tonnes per hectare and produce approximately 12,000 new seeds returned to the seedbed for future crops.”
Animations
New animations developed by Bayer CropScience aim to help growers make the most of pre-emergence sprays.
Click here to view animations
Herbicides campaign manager at Bayer CropScience, Phillippa Overson says: “We recognised the extent of the black-grass problem and the importance of pre-ems in controlling the weed. We felt a short punchy video would create the most impact and meant farmers would not have to trail through lots of information.
“The animations give a general overview on how to best deal with black-gras,s for example when to apply pre-ems, the importance of a stale steel bed, how deep to drill. It's early days but the animations have received a lot of Twitter attention and so we are optimistic they will be a success.”
Steps for optimum weed control
- Create the best possible seedbed - drill crops to 32mm
- Delay drilling to hit peak black-grass germination
- Apply pre-emergence herbicides within 48 hours of drilling
- Always apply Liberator at full rate
- Use appropriate tank mixer partners
- Use sufficient water volume to achieve coverage
- Apply using the best possible spray techniques
Source: Bayer CropScience
Previous Article Details emerge of Wales' EU dairy package
Next Article Raymond to represent EU farmers in supply chain talks